What's the point of all this talk? The point is that the military was poor before the First World War, and afterward the politicians thought that we wouldn't need a strong army so they cut the budget even more.
So the military had to save money as much as possible. Therefore when a new uniform was introduced they didn't throw away the old ones, nothing was wasted. Instead they used the old ones until they were beyond repair and then you could get a new uniform. Because of this you can see soldiers mixing different uniforms in the same unit.
Soldiers wearing uniforms m/ä
The oldest uniform is called modell äldre (m/ä, model older), and that's the name all uniforms before the fm/06 uniform (more about that one soon) got. The m/ä uniform was not identical in the whole army; different units had different looking m/ä uniforms. You can here see the different models.
How to convert from m/23 to m/ä: They are very similar so you will only need to cut away the four front pockets with a sharp knife! This uniform did also have more buttons.
Next model is called fm/06 (test model 1906, försöksmodell 1906). The idea was to get a modern unity uniform, one that the whole army would use, instead of having many different. Here are some of the sketches of what the new uniform would look like. Some ideas was used from the sketches, some not. You can see that they were heavy inspired by the look of the Swedish soldiers of the Great Northern War.
The fm/06 uniform evolved into the m/10, which was the official uniform until 1923 for the army and from the First World War until the Second for Landstormen (Home Guard).
But more about the m/10 at a later point.
How to convert from m/23 to fm/06: Cut of the epaulettes.